Weed growers pose a significant obstacle in the quest to gather information about how much electricity is used within cities and neighborhoods, said Ethan Elkind, climate research fellow at the University of California, Berkeley's School of Law. The state wants those regional data on power consumption to better target power-curbing solutions.

People who grow pot illegally fear that disclosures about electricity could point to their operations because they tend to use larger amounts of power, Elkind said. The indoor marijuana farms, often found in basements, must employ high-powered electric lights called grow lamps that use far more electricity than ordinary light bulbs.

"Overall, most people have little to hide when it comes to electricity usage," Elkind wrote in a blog post Monday. "But indoor marijuana growers sure do, and they are quietly constituting a major force in opposition to greater disclosure of energy data. They have reason for concern. In documented cases, police have issued subpoenas for electricity data to bust pot growers."

Elkind's post arrived as activists in the Golden State work to put measures on the ballot that would legalize marijuana for recreational use, efforts similar to those that passed in Colorado and Washington state in 2012. Three would-be propositions for California have been approved to gather voter signatures, and a fourth is waiting for approval from the state Office of the Attorney General. Each would need 504,760 names counted and verified by June 26 to make it on November's ballot. The state already allows marijuana for medical purposes.

Meanwhile, groups in Oregon and Arizona also are gathering signatures to get legalization measures on upcoming ballots. Alaska has a marijuana legalization measure slated for its Aug. 19 vote. When Public Policy Polling last month asked 850 registered voters in Alaska whether "marijuana should be legally allowed for recreational use," with sales "taxed and regulated similarly to alcohol," 55 percent said "yes," 39 percent said "no," and 6 percent said they were unsure. The survey had a 3.4-point margin of error.

The pot question is important, Elkind said, because in California, officials have been urging a release of utility data. Having broader energy user information could mean both power and cost savings, Ken Alex, senior adviser to Gov. Jerry Brown (D) and director of the state's Office of Planning and Research, said in a blog post last summer on Legal Planet, where Elkins also wrote.

"Right now, we do not have answers to some very basic questions," Alex wrote. "What neighborhoods use the most energy? Which industries? What are the load shapes for usage in downtown Los Angeles? Where are the distribution line bottlenecks?

"California utilities have the data to answer these questions," he added. "It is time that regulator and the public -- with safeguards for privacy -- have access to that data. It is an essential piece to addressing the climate change puzzle as we transition to a carbon free energy system."

Environmental questions linger

Legalizing marijuana for recreational use remains controversial. California Police Chiefs Association Executive Director Leslie McGill in an email said, "We do not support legalizing marijuana. For any reason." The association would oppose any weed legalization initiative that landed on California's ballot, McGill said.

Recent polls show a slight majority of Golden State residents support ending state prohibition. A Field Poll in December found that 56 percent of California voters favored legalization, while 45 percent opposed it. The poll of 1,002 registered voters had a 3.2-point margin of error.

At the same time, there's been concern about marijuana's impact on the environment, beyond electricity use. Some farmers of food crops have accused medical marijuana growers of polluting water and exacerbating California's drought. Marijuana farmers divert water from streams illegally and bulldoze hillsides to grow crops, dumping soil into the water (Greenwire, Jan. 30). Gov. Brown included $3.3 million for enforcement of laws related to marijuana growth in his proposed 2014-15 budget.

In Congress, a bipartisan group of California lawmakers has urged the U.S. Sentencing Commission to respond to the environmental harm caused by illegal marijuana growers on public and private lands (Greenwire, Nov. 27, 2013). Environmental advocates have expressed concerns about illegal growers moving onto public parklands, using pesticides and diverting water.

But some marijuana legalization backers see the possibility of an alliance with green groups.

"There's no doubt that we're at an interesting time where the environmental movement now can feel more comfortable working with marijuana law reform," said Allen St. Pierre, executive director of the National Organization for the Reform of Marijuana Laws, or NORML, a Washington, D.C.-based lobbying group. "There's a very cogent argument to be made that by joining forces, we can reduce energy consumption and not potentially harm our natural lands by people who are going outside of the law."

It's potentially a significant amount of power, Elkind said. A 2012 study by Evan Mills of the Lawrence Berkeley National Laboratory "indicated that these grow operations could be responsible for up to 2 percent of nationwide household electricity usage, at a total cost of $6 billion," Elkind said in his blog post.

Accessing data difficult

There have been preliminary efforts looking at accessing utility users' consumption information. The California Public Utilities Commission has a proceeding "evaluating mechanisms for the utilities to provide data to the public while protecting privacy," Alex with the governor's office said in his post.

But some utilities have said they're not eager to give information. And privacy controls might not be enough to ease the concerns of marijuana growers, said John Lee, one of the backers of the "Marijuana Control, Legalization and Revenue Act of 2014," which is gathering signatures in a bid to make the fall ballot. The effort just signed a $500,000 agreement with an independent contractor to obtain signatures.

"Certainly, there's a concern from any grower about reporting and providing information," Lee said. "Illegal growers are the ones we're trying to address and put aboveboard" with the state legalization bid.

Both Elkind and St. Pierre, however, said that state laws legalizing marijuana use probably won't be enough to bring all illegal growers and their electricity information into the light. Without the federal government acting, those people likely still would fear criminal penalties if power use information hinted at their activities, St. Pierre said.

"Technically, as long as the federal government still considers this illegal, there will be some that don't want to comport because they don't want to expose themselves to prohibition," St. Pierre said.

Elkind also said that beyond marijuana growers, there have been other fears about privacy, including that utility information would reveal when people are home. But he said the data can be aggregated in a way so that they don't show information about individuals.

Research progresses in L.A.

Elkind and Alex both pointed to the importance of one small study of power use by neighborhoods already underway in California. Alex in his blog post called it "hugely important to understanding how we can increase energy efficiency, both by end users and by utilities."

The Los Angeles Department of Water and Power has released seven years' worth of electricity and 10 years of water data to the University of California, Los Angeles. The school aggregated the information -- which originally was tied to addresses -- and examined it at a census tract level, said Stephanie Pincetl with the California Center for Sustainable Communities at UCLA.

UCLA added in information about income, size of buildings and age of buildings. Pincetl said the school wanted to see how weather, household income, age of buildings and size of buildings affect power use. UCLA created an interactive map of electricity consumption that shows use over time by neighborhood.

"Unless you have the granular data and analysis, it's very difficult to know what's going on," Pincetl said. She added that "we're trying to find out what is the most significant factor in the energy use patterns we see in order to be able to guide the next investments in energy conservation and efficiency."

The researchers followed guidelines to keep information anonymous, she said. Those included throwing out data when a neighborhood had fewer than 15 residents or disregarding a block when one user consumes more than 15 percent of average.

It's the type of study that could be done more broadly if there were other utility data available, Elkind said. The state could then micro-target incentives for people to conserve, he said.

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